Calculating the total CO2 emissions related to a particular product is actually quite a challenge.

Thanks to Carbonfund.org, we've been able to install their carbon calculator to help you, but you can only use it for a small part of the overall total. You will also need to load up several other links as separate windows (right-click on link and select 'open in new tab') to give you some of the tools you need.

Simple Calculation

Having chosen a product and looked up its country of origin (final assembly) on this site, you can then use another shipping distance calculation tool to calculate the distance between the nearest ports if the product is travelling by ship. A good one is at www.portworld.com – it's fast and well thought out.

Here are some popular distances, using Yantian port in China as the source of the product, as it's used by many Shenzhen OEM manufacturers like Hon Hai, who make most of Apple's products, all main games consoles and so on:

Yantian Port, China, To:
New York, USA 11254mls/18112km
Los Angeles, USA 6400mls/10300km
London, UK 9564mls/15392km
Marseilles, France 7960mls/12810km

Then you'll need to look up the transport distance from the port to your home location. These sites are quick to use and convenient.

http://www.distance-calculator.co.uk/usa-distance-calculator.php
http://www.distance-calculator.co.uk/distance-calculator.php#chosentown

You'll then need to work out the approximate weight of the product. Here are some popular examples of products with approximate weights to help you:

Netbook 4.4lbs/2kg
Laptop 5.5lbs/3kg
Scooter 220lbs/100kg
Large Motorbike 470lbs/213kg
Toyota Sienna 5,690lbs/2581kg

With the weight of the product, you can then use the site's carbon calculator by clicking on 'CO2 Guide,' at the top of the Search Results box. Then select 'Shipping' in the 'Emissions Source' menu, to work out the transportation CO2 costs of your product in several stages, and then add them together. If you need a converter between measurements, there's one at www.onlineconversion.com that works well.

The calculator also has direct links to the carbonfund.org site if you want to explore other options like offsetting for the result you get.

However, it is a very basic calculation, and will probably look surprisingly small. This is because it can only take into account the individual product. For a more accurate calculation, there's a lot more research to do!

Supply Chain Calculation

Calculating the whole CO2 costs associated with a particular product needs a lot of research, and even then, with only some of the information publicly available, you'll still only arrive at a rough guide figure. Some parts of the calculation are not really possible to do unless you're part of the companies and countries concerned.

1. Product Design/R&D

The operation of an R&D centre will have its own CO2 costs in energy, employee travel, and so on. Once the product is finalised, the next stages can be looked at.

2. Resources and Component Sourcing

In a vertically integrated company, this will be done in-house and will be easier to track. Many corporations outsource though and this will lead to a web of component sources. These component manufacturers will all need access to the resources they need, and to transport them to the production plant, with its own energy and employee totals. The production of the energy (eg coal) will also have separate costs.

3. Product Assembly

The components will need to be transported to the assembly plant, which will have its own energy and employee costs.

4. Product Shipping

Finally the product can be shipped to its destination, although this is likely to be a holding warehouse and then a store before it gets to you. It's a simplified (ie direct) version of this section that the Simple Calculation above does.

5. Product Useage

This section is usually covered by both the energy efficiency rating of the product, the way in which you use it, and how the energy needed to use it is generated.

6. Product Disposal

The CO2 costs involved in the disposal of the product can be reduced by recycling some of its components, but for highest efficiency this has to be designed-in at the development stage.

Of these 6 separate stages of CO2 production, only the 4th and 5th can be calculated with any accuracy by an ordinary person, without access to often confidential company information and records. Fortunately more and more retailers and manufacturers are trying to devise more open CO2 accounting systems, and there are lots of guidelines on how to do it available on the net to look at. There are also many Green Supply Chain sites which look at the problems raised here in more detail.

Further Complications

The CO2 costs of an individual product are hard to separate from the mass production of products, the transportation of a container of products (or a shipload of 2000 cars, for example), the retailer's warehouse useage for thousands of other products and so on.

Then there's the feedback issue: your purchase of a popular product may be part of a boost in sales which leads to an increase in production and therefore an increase in all the emissions above. It will also increase demand for energy from the local supplier, and this may have repercussions for the future in terms of how that energy will be produced over the long-term (coal, nuclear, renewables and so on). So giving your product a clear CO2 total is actually quite difficult.